Patent · US Expired

Precious metal recovery using thiocyanate lixiviant

US7285256B2 · kind B2 · utility

12Cited by
17References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 28, 2003
Grant dateOct 23, 2007
Priority date
Expiry dateOct 1, 2024

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/20
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Precious metal-containing mineral material is subjected to an acidic thiocyanate leach to dissolve the precious metal as a precious metal-thiocyanate complex. A feed of the thiocyanate leach solution may include a large molar ratio of ferric iron to thiocyanate. Precious metal may be removed from pregnant thiocyanate leach solution, such as by transferring precious metal from precious metal-thiocyanate complex to precious metal-cyanide complex and then loading the precious metal-cyanide complex onto an adsorbent material. Remaining cyanide in the thiocyanate leach solution may be converted to thiocyanate for additional leaching of precious metal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.